This invention relates to water-absorbent polymers which are known in the art as "superabsorbent" polymers. These polymers have the capability to absorb large volumes of aqueous fluids and find use in the manufacture of disposable diapers, sanitary napkins and incontinent devices. Superabsorbent polymers are prepared from at least one monomer having a polymerizable double bond which is water soluble or which becomes water soluble upon hydrolysis. Examples of such polymers are crosslinked, partially neutralized, polymers and copolymers of acrylic acid, starch grafted, polymers and copolymers of acrylic acid polymers and starch-polyacrylonitrile grafted polymers. The preparation of such polymers is well known in the art; see for example U.S. Pat. No. 4,076,663 which describes the solution polymerization of starch grafted, acrylic acid polymers.
Superabsorbent polymers are prepared on a commercial scale by solution or suspension or emulsion polymerization processes. In the suspension or emulsion methods, the monomer is polymerized in the form of droplets dispersed in a non-aqueous suspension medium and recovered as fine particles of spheres. In the solution method, the monomer is polymerized in water to produce a high viscosity gel which is extruded into strands or films which are dried to remove the aqueous polymerization solvent and ground into particles. In this grinding step, fine particles (&lt;75 microns) are produced which are undesired because they have poor fluid absorbency properties and they cause dusting problems in the fabrication processes for preparing end products. This invention is directed to polymers prepared by the solution polymerization method. It is the object of this invention to recycle undesired fine particles produced in the grinding step and to reform them into larger more useful particles.